High Copper Alloys- Lets discuss this further

[MostlyOnThePaper]

I am definitely looking forward to it!!! I hope it's on a weekend I have off, that I can contribute more to the fun and hopefully stay for the whole thing instead of just showing up on Saturday... I learn so much from y'all I just have to worry about my head exploding!

I look forward to it, thanks.

I'm not nearly as experienced or bright as you guys when it comes to this stuff, but I am a good study. I'll try to keep good notes on what I'm doing so hopefully I'll have something to contribute.

I just wish I knew the makeup of this soft lead I have that I recovered from commercial jacketed pistol bullets. Melt temp and coloring when heated points to something very close to pure lead but Mike's trained ear says it has a bit of a Sb ring to it when you drop the ingots. I've been treating it as pure lead for my 50/50 water dropped stuff.

[badgeredd]

poppe

[btroj]

Intermettalics can change over time. Look online, there are many studies involving solder and the intermetallics formed when solder is joined to copper.
I don't think our alloys stabilize right away. This is where changes in size and / or hardness come from.

[bearcove]

The silver solder we use a lot is 99+%tin a bit of silver and 0.4% copper.

Arsenic might be a big factor for toughness. We have had alloy made for group buys with 0.25% arsenic. For that reason.

[nanuk]

In the end we may not have the ability to totally understand WHY something happens. I am happy enough to know WHAT happens. Knowing what to expect, when to expect it, and how to deal with its good enough to me.

isn't that kinda what Internal Ballistics is?

an edjumkated guess?

[btroj]

Pretty much. We use observation and analysis to figure put what, in general, works.

[bearcove]

Read some stuff I hadn't and see better where this discussion is, and If you want to think about As Cu as grain refiners in the crystaline structure in realtion to toughness I think that might be as far as it goes. Fine grain structure will give you more fracture resistance than a course structure. Don't know if there is any magic past that.

[bearcove]

As far as "toughness" goes it might be that fine grain structure may give you your ultimate "toughness" for the hardness you require for lack of deformation in a Large meplat terminal balistic situation. If thats what we are working.

[303Guy]

Well folks, I've just tested a copper toughened boolit (outside the bathroom into my test tube, right under the neighbours noses) and the results are - well, a bit disappointing. Way too much penetration and nothing to recover for examination. In short, the boolit shot right through double catch medium and disintegrated against the 4140 steel bottom container base (the first of two). Mind you, the boolit was pretty hard when I checked it before firing (can't tell you the hardness - I use a different measuring system that has no reference as yet). It is the same alloy that I beat into a disc a week or two ago. This alloy has been quietly hardening since first casting.

Oh, it wasn't exactly a slow boolit. I shot it with a full case of W780 and pressure signs indicate a moderate pressure load. The boolit was 201gr and the barrel 25 inches (303 Brit of course).

[runfiverun]

how much did the boolit grow from when it was cast?

[303Guy]

These won't go back into the mold! I didn't measure as cast so can't tell. I bet it's solved the nose slump/upset problem. I should try a hollow nose in the medium. I did cast some flat nose which I'm sure would work fine for hunting. It's going to be a few weeks before I can get out to the range with a chronograph. In the meantime I'll cast up few more and measure them. Then I'm going to empty the pot into ingots (fishing sinker molds) and try toughening COWW's and see what happens.

I should test fire into soft sand like I've done before.

[runfiverun]

i'm just data gathering is all.
i have heard some reports of around 10% growth.

[btroj]

10%!!!!!!
That means a 30 cal becomes a 338 bullet!
I could believe 1% but 10%? That seems a bit hard to believe.

Not questioning You Run, just the reports of that much growth.

[swheeler]

Just under .5% growth for 30 days on .9% cu alloy for me

[357maximum]

I have yet to see over a .8 to .9% and that was after waterdropping and hot storage for 6months .

[runfiverun]

grrr fat-fingered the board again disregard the zero..
1%.

[303Guy]

303guy - any idea of the alloy Sn/Sb/Cu %s? Your fps should be > 2400 (?).

I did work it out with the copper being an unknown but I can't find it! I did post it under the copper sulphate thread.

[303Guy]

If this alloy grows in time then is it wise to leave it solid in the melting pot? I'm referring to a Lee drip-o-matic.

[303Guy]

303guy - any idea of the alloy Sn/Sb/Cu %s?

Here it is;

90% Pb, 6.8% Sn, 1.8% Sb, 1.5-2% CU

The copper is a guess, it could be less than 1%. Actually, the whole set of numbers are uncertain being based on known #11 Babbit and thought to be lino but which could be melted down pewter for all I know (but seems unlikely since no-one melts down pewter ware into ingots then sells it off as scrap metal to a recycler). The tin level does seem probable if not accurate.

[Iowa Fox]

I might have missed it along the way but Edd what is your railroad babbit? Thirty years ago we had one junk dealer scrapping old railroad cars here. The old cars had babbit axle bearings and I was lucky enough to get 50 lbs of it. Is that the same stuff as yours?